1. Field
The present disclosure relates to cutting heads for rotary trimmers and, more specifically, it relates to an improved cutting head for rotary trimmers using continuous lengths of spooled monofilament strings as a means for cutting vegetation. The present disclosure represents an improvement over presently existing cutting head designs and allows for quick, smooth, ratchet-type efficient loading of the monofilament strings onto the spool of a cutting head.
2. Description of the Related Art
Flail feedout means for mowing and trimming devices used to trim grass, weeds, and other vegetation, of the rotary type equipped with flexible cord-like flails formed of generally cylindrical fibers, are well known in the art. Grass and weed cutters of this general type are widely known and the subject of various patented devices including those described in Ballas et al., U.S. Pat. No. 3,826,068; Mizuno et al., U.S. Pat. No. 4,020,552; Prouix, U.S. Pat. No. 4,097,991; Perdue, U.S. Pat. No. 4,134,204; Toro, Belgium Patent No. 852,150; and Prouix, U.S. Pat. No. 4,259,782. Such devices are available on the market having automatic flail feedout mechanisms which respond to a bump on the ground intentionally applied by the operator or by the application of force applied thereto by some mechanical arrangement.
An improved flail feedout mechanism for a rotary mower is disclosed in the above-mentioned U.S. Pat. No. 4,259,782, the disclosure of which is incorporated herein by reference. However, the specific construction of the tangs and the serpentinous cam slot in that device is designed to result in stress concentrations in the engaging members and, as a result, an abrupt and discontinuous operation of the feedout assembly occurs which results in potential wear of the assembly parts, as well as non-smooth operation of the mowing device.
Applicant is the inventor of U.S. Pat. No. 6,735,874 B2 which issued on May 18, 2004 and is entitled “Cutting Head for a Rotary Trimmer”. U.S. Pat. No. 6,735,874 is incorporated in its entirety herein and basically discloses a handle with an attached drive means that is connected to a spinning housing. The housing has a spool containing one or more coils of string used as filaments for cutting vegetation. A pair of orifices is oppositely positioned on the spool for guiding the exposed filament to the proper cutting position.
The feed-out assembly of U.S. Pat. No. 6,735,874 is disclosed in detail in said patent and operates smoothly so that its performance does not degrade with use. Also, the assembly operates in a smooth and consistent manner, without resulting in stress concentrations on individual parts forming the feed-out assembly, as was the shortcoming in the prior art.
Although the cutting head disclosed in U.S. Pat. No. 6,735,874 operates in an efficient and smooth manner, a need exists for a cutting head that can be quickly and easily loaded with a length of flail. A further need exists for a cutting head for a rotary trimmer that can be loaded without requiring disassembly of the cutting head.